Hillary Clinton is meeting with diet guru Dr. Mark Hyman — who’s credited with turning around Bill Clinton’s health — as she prepares for a 2016 presidential run. She was spotted dining with Hyman at the West Street Grill in Litchfield, Conn., Sunday night. Sources say Hillary, who was accompanied by four Secret Service agents and two troopers, drove an hour from her home in Chappaqua for the three-hour dinner with Hyman and his girlfriend. Hyman runs the Ultra Wellness Center in Lenox, Mass., which helps promote healthy weight and metabolism. The center’s Web site home page includes an article titled, “How hidden food sensitivities make you fat.” Hyman also wrote the book “The Blood Sugar Solution.” Bill Clinton, who lost 24 pounds in less than two years on a vegan diet he started in 2010, endorsed the book: “I’ve made drastic changes to my own diet and exercise routine since my heart troubles surfaced in 2004, and I hope Dr. Hyman’s new book will inspire you as he has inspired me.” An inspired Hillary ate a healthy meal of grilled salmon and seasonal fruits. Later she posed for pictures with eatery owners James O’Shea and Charlie Kafferman, and chatted with architect Gregorio Alvarez and well-coiffed broadcaster Bill O’Shaughnessy about Zahir Ziani, the hair stylist they both share at the Red Door Salon in New York. Hyman told other diners, “We picked the West Street Grill because I had my first date here and it was halfway for both of us. Hillary and I each had to drive an hour.” A rep for Hillary, who suffered a health scare at the end of last year when doctors discovered and successfully treated a blood clot near her brain, didn’t get back to us.